State of the Global Climate 2020: WMO | 21 Apr 2021

Why in News

Recently, the World Meteorological Organization (WMO) released its annual State of the Global Climate for 2020.

  • The report was released ahead of the Leaders Summit on Climate, hosted by the US.
  • Extreme weather combined with Covid-19 was a double blow for millions of people in 2020. However, the pandemic-related economic slowdown failed to put a brake on climate change drivers and accelerating impacts.

Key Points

  • Global Temperature:
    • 2020 was one of the three warmest years on record, despite a cooling La Niña event.
      • The global average temperature was about 1.2° Celsius above the pre-industrial (1850-1900) level.
      • The other two warmest years are 2016 and 2019.
    • The six years since 2015 have been the warmest on record.
      • 2011-2020 was the warmest decade on record.
  • Greenhouse Gases:
    • Emission of major greenhouse gases increased in 2019 and 2020.
      • It will be higher in 2021.
    • Concentrations of the major greenhouse gases in the air continued to increase in 2019 and 2020.
    • Globally, averaged mole fractions of carbon dioxide (CO2) have already exceeded 410 parts per million (ppm), and if the CO2 concentration follows the same pattern as in previous years, it could reach or exceed 414 ppm in 2021.
      • Mole fraction represents the number of molecules of a particular component in a mixture divided by the total number of moles in the given mixture. It's a way of expressing the concentration of a solution.
  • Oceans:
    • In 2019, the oceans had the highest heat content on record. In 2020, it has broken this record further. Over 80% of the ocean area experienced at least one marine heatwave in 2020.
      • A marine heatwave is defined when seawater temperatures exceed a seasonally-varying threshold for at least 5 consecutive days.
    • The percentage of the ocean that experienced “strong” marine heat waves (45%) was greater than that which experienced “moderate” marine heat waves (28%).
  • Sea-level Rise:
    • Since record-taking started in 1993 using the satellite altimeter, sea-level has been rising. It is due to the La Niña induced cooling.
    • Sea level has recently been rising at a higher rate partly due to the increased melting of the ice sheets in Greenland and Antarctica.
  • The Arctic and the Antarctica:
    • In 2020, the Arctic sea-ice extent came down to second lowest on record.
      • The 2020 minimum extent was 3.74 million square kilometre, marking only the second time (after 2012) on record that it shrank to less than 4 million sq km.
    • In a large region of the Siberian Arctic, temperatures in 2020 were more than 3°C above average.
      • A record temperature of 38°C was noted in the town of Verkhoyansk, Russia.
    • The Antarctic sea-ice extent remained close to the long-term average.
      • However, the Antarctic ice sheet has exhibited a strong mass loss trend since the late 1990s.
      • This trend accelerated around 2005, and currently, Antarctica loses approximately 175 to 225 Gigaton per year, due to the increasing flow rates of major glaciers in West Antarctica and the Antarctic Peninsula.
  • Extreme Weather Events in India:
    • India experienced one of its wettest monsoons since 1994, with a seasonal surplus of 9% that led to severe floods and landslides.
    • Cyclone Amphan, which hit Kolkata in May 2020, has been named as the costliest tropical cyclone for the North Indian Ocean region that brought about an estimated loss of USD 14 billion.
  • Climatic Impact:
    • Extreme Weather Situations:
      • Along with the pandemic, people across the world struggled to survive as they faced extreme weather in the form of storms, cyclones, heavy rainfall and record heat.
      • Response and recovery to people hit by cyclones, storms and similar extreme weather was constrained throughout the pandemic in 2020.
    • Human Mobility Issues:
      • Mobility restrictions and economic downturns owing to Covid-19 slowed down delivery of humanitarian assistance to vulnerable and displaced populations, who live in dense settlements.
      • The pandemic added further dimension to human mobility concerns, highlighting the need for an integrated approach to understanding and addressing climate risk and impact on vulnerable populations.

World Meteorological Organization

  • About:
    • It is an intergovernmental organization with a membership of 192 Member States and Territories. India is a member.
    • It originated from the International Meteorological Organization (IMO), which was established after the 1873 Vienna International Meteorological Congress.
  • Establishment:
    • Established by the ratification of the WMO Convention on 23rd March 1950, WMO became the specialized agency of the United Nations for meteorology (weather and climate), operational hydrology and related geophysical sciences.
  • Headquarters:
    • Geneva, Switzerland.

Source: DTE